Many thanks key_master
1) Will there be any adverse effect if I change the environment to Deny,Allow?
2) Is ok to use the Limit container rather than the Files container?
3) My inclination towards mod_rewrite was because of the capability of coordinating IP's and UA's for the SE's. (We have some make fake SE UA's these days, as well as the SE's themselves (from the same IP's) using standard or malformed browser UA's.
BTW, saw your thread in the other forum.
Your to be commended for another superb and time intensive effort.
That forum and since Jim's absence seems to be comprised of a few devotees attempting to help Jim, while most of the inquires are from newly registered users. I'd almost wager that forum attracts more noobs than any other forum at Webmaster World.